The present invention deals with a gummed paper taping unit with improved guidance of the paper in the dampening zone.
Gummed paper taping units are used in carton sealing machines for delivering and applying short lengths of paper with moistened gummed faces onto the tops and/or bottoms of boxes.
Known gummed paper taping units, described in EP-A-0558122 and EP-A-0579329, comprise substantially a supporting means for a reel of gummed paper, a feeding means for extracting a continuous strip of gummed paper from the reel and having it move along a predetermined path with an oblique terminal portion, a cutting means situated substantially at the end of the oblique path portion for the purpose of cutting the continuous strip into single lengths of gummed paper, a paper path-deviating means for positioning the paper in a vertical direction at the end of the oblique path portion, a dampening means with moistened bristles set downstream of the deviation means for dampening the gummed paper lengths and a means for applying the gummed paper lengths onto the top or the bottom of a box.
In the taping units the means for deviating the paper is made up of at least two co-operating guide pads which are placed one upstream of the other in the direction of the forward movement of the paper, and define an arcuate path portion for the paper and, downstream thereof and in front of the dampening group, a resting plane for the paper undergoing the dampening treatment.
It has been possible to verify that the solution presently being used is not completely fit for very light gummed paper. As a matter of fact, in this case it can happen that the paper coming out of the upstream guide pad crinkles or is subject to other distortions and hence does not reach the desired correct engagement with the bristles of the dampening means. The taping unit jams up or, at the least, emits deformed paper lengths which are not fit for a correct sealing of the box.